2-methyl - 5-phenyl-1 2-dihydro-3h-2-benzazepine or a salt thereof and process for preparing same

ABSTRACT

THE COMPOUND 2-METHYL-5-PHENYL-1,2-DIHYDRO-3H-2BENZAZEPINE AND SALTS THEREOF ARE PROVIDED AS WELL AS A PROCESS FOR THEIR PRODUCTION BY THE CYCLIZATION OF 3-(NBENZYLMETHYLAMINO)-1-PHENYL-PROP-1-YNE. THE COMPOUND HAS A SEDATIVE-HYPONTIC EFFECT.

Uflilfid SUItES Pat '51 3,655,651 Z-MEL S-PHENYL-1,2-DlHYDRO-3H-2-BENZ- AZEPTNE OR A SALT THEREOF AND PROCESS FUR PREPAG SAME David N. Harcourt and James R. Brooks, Bath, England,

lassidgnors to Allen & Hamburys Limited, London, Engan N Drawing. Filed Mar. 5, 1970, Ser. No. 16,960 Claims priority, application Great Britain, July 17, 1969, 36,02'7/69 Int. Cl. C07d 41/08 U.S. Cl. 260-239 BB 6 Claims ABSTRACT or ran nrsc The compound 2 methyl-S-phenyl-1,2-dihydro-3H-2- benzazepine and salts thereof are provided as well as a process for their production by the cyclization of 3-(N- benzylmethylamino)-1-phenyl-prop 1 yne. The compound has a sedative-hypnotic effect.

This invention relates to a novel benzazepine derivative.

We have found that the cyclization of compound 3-(N- benzylmethylamino)-l-phenylprop-l-yne (I) leads unexpectedly to a novel benzazepine derivative II:

1 /N NMe a} 1 1 I Me ll (Ph =pheny1 Me=methyl) III by hydration of the triple bond. Cyclisation with anhydrous aluminium chloride resulted in the compound of Formula II. The cyclisation is best effected therefore using anhydrous aluminium chloride or a similar cyclising agent.

The cyclisation is preferably effected in the presence of an organic solvent as suspending agent. Suitable or- 3,655,651 Patented Apr. 11, 1972 EXAMPLE 3 (N-benzylmethylamino)-l-phenyl-prop-1-yne (10 g.) was dissolved in chlorobenzene ml.) and anhydrous aluminium chloride (20 g.) added. The suspension was refluxed for 6 hr., cooled, and water cautiously added. The chlorobenzene was separated and washed with dilute hydrochloric acid, the washings being returned to the aqueous solution. The latter was basified with sodium hydroxide (20%). Extraction yielded basic material (5.3 g.). The fraction of RP. 146-148/0.55 mm. (2.5 g.) was the required product.

The picrate, needles from ethanol, had M.P. 209- 210 (Found (percent): C. 59.6; H, 4.4; N, 11.9. C H N O requires (percent): C, 59.5; H, 4.3; N, 12.1).

What is claimed is:

l. The compound Z-methyl-S-phenyl-1,2-dihydro-3H- Z-benzazepine or an acid addition salt thereof.

2. A process for the preparation of 2-methyl-5-phenyll,Z-dihydro-3H-2-benzazepine which comprises cyclizing a compound of the formula Nile in which Ph represents phenyl and Me represents methyl in the presence of anhydrous aluminium chloride as cyclizing agent.

3. A process for the preparation of 2-methyl-5-phenyl- 1,2-dihydro-3H-Z-benzazepine which comprises cyclizing 3-(N-benzylmethylamino)-l-phenyl-prop-l-yne in chlorobenzene with aluminium chloride under reflux and recovering the product as the free base.

4. A process as claimed in claim 2 in which Z-methyl- 5-phenyl-1,2-dihydro-3I-I-2-benzazepine is recovered in the form of the free base.

5. A process as claimed in claim 2 in which Z-mcthyl- S-phenyl-l,2-dihydro-3H-Z-benzazepine is recovered in the form of an acid addition salt thereof.

6. A process as claimed in claim 5 in which Z-methyl- 5-phenyl-1,2-dihydro-3H-2-benzazepine is recovered as the picrate.

References Cited UNITED STATES PATENTS 3,225,031 12/1965 Sherlock 260239 3,242,164 3/1966 Sherlock 260-239 OTHER REFERENCES Brooks et al., J. Chem. Soc. (London), Part C, 1969, pages 625627 (Scientific Library).

ALTON D. ROLLINS, Primary Examiner U.S. Cl. X.R. 260-999 

